[The adult respiratory distress syndrome]

Adult respiratory distress syndrome may be caused by a large number of injurious agents. In the pathogenesis the damage to endothelial cells and membranous pneumocytes is most important. While the etiology is diverse, the pathology may be rather uniform, beginning from acute "exudative" stage, characterized by protein-rich interstitial and alveolar edema, and progressing to a subacute "proliferative" stage, ending in interstitial, and sometimes intraalveolar fibroplasia, together with alveolar cell hyperplasia. But secondary lesions and complications make the proper diagnosis based on morphological criteria quite difficult. A retrospective study of 20 autopsies of patients who died from adult respiratory distress syndrome after various causes is dealt with. Some difficulties with diagnostic criteria based on morphologic features alone are discussed, and the necessity of clinical and pathological correlations is emphasized.